Mouth guards have been developed and sold for several years for use in connection with contact sports such as football and hockey, and other activities. Several prior art mouth guards comprise a U-shaped base member with inner and outer flanges that extend upwardly to surround the wearer's upper teeth. Such mouth guards cushion the impact of the upper and lower teeth and protect the teeth in response to jarring action or impact. Several prior art mouth guards are made from ethylene vinyl acetate (EVA), which is a softenable thermoplastic. EVA's softening point is less than the temperature of boiling water. Therefore, such a mouth guard may be formed, or custom fit, to the wearer's mouth by placing the mouth guard in hot water until it becomes soft, and then placing it in the wearer's mouth. Such a mouth guard retains the shape of the wearer's teeth and mouth upon cooling.
A traditional mouth guard for individuals with braces is simply placed in the wearer's mouth. Currently marketed mouth guards for braces or other dental appliances are composed of medical grade silicone, or other high temperature materials that cannot be heated or boiled for fitting around the teeth and gums. One example is disclosed in U.S. Pat. No. 5,954,500 (Spriggs). Because such traditional mouth guards cannot be fitted, they tend to move around in the mouth, making it difficult to breathe and speak, and they fail to provide adequate protection, depending at least in part upon the position at the time of impact. However, if EVA or a similar low temperature melting plastic were used, for example, the softer plastic could easily become entangled with the braces and cause damage or inconvenience such as shifting or pulling wires. Because every mouth has a different shape, a non-fitted mouth guard is inadequate for a great number of wearers. In addition, impact absorption increases with improved fit.
Multiple molding of mouth guards is not new. For example, in U.S. Pat. No. 6,508,251 (Kittelsen), multiple layers of softenable/non-softenable material are disclosed. However, the layer(s) which come in contact with the teeth (or, if a user has braces, with the braces) are made of a moldable material such as EVA, methyl methacrylete, chlorosulfonated polyethylene, fluoridated methacrylate, methacrylic acid or photo initiators. In U.S. patent application Ser. No. 10/232,240 (Publication No. 2003/0019497) (Farrell), a polyethylene “base member” is “encased” within EVA. Thus, the EVA portion, which is softenable and moldable, would come into contact with the teeth or braces. However, the prior art does not disclose a multiple-molded mouth guard with a softenable, custom fit horizontal tooth bearing surface together with a non-softenable vertical upper portion which comes in contact with braces or other dental appliances.
There is a need, therefore, for an improved mouth guard which may be fitted or formed for users having braces.